Isolating High MW DNA from Gel- Best Way??

[Peter T. Boag]

We are doing some genomic library building and want to
preferentially clone fragments in the 5 to 15 kb range. We have
experimented with various ways to isolate this range of DNA from an
Agarose gel, and always seem to end up with a low yield. We have
tried inserting  a piece of dialysis membrane and running the DNA
onto it. We have cut a well in the gel ahead of the desired area,
then pipet off the DNA as it runs into the well.  We are thinking
now of excising the relevant piece of gel and spinning it above a
siliconized glass wool plugged 	eppindorf with a hole in the bottom
inserted into a second eppindorf, and collecting the runoff (this is
a variant of the "freeze and squeeze" approach).

Any suggestions for this type of isolation, either quit and dirty or
fancy commercial approaches such as these electroelution chambres??
Thanks, Peter
******************************************************************
********************

Peter T. Boag			TEL: (613) 545-6160
Department of Biology		FAX: (613) 545-6617
QueenÕs University			EMAIL: BOAGP at QUCDN.QUEENSU.CA
Kingston, Ontario
Canada  K7L3N6

******************************************************************
********************